As technology has progressed, biometric features are increasingly being used in consumer electronics for user identification and customized usage. In particular, fingerprint authentication has been added to smartphones, tablets and other devices, to increase security and avoid the trouble of inputting an authentication password by a user via keyboard or touchscreen. In fingerprint authentication, the fingerprint of a user is acquired through a fingerprint sensor, and when a similarity between the acquired fingerprint and a stored reference fingerprint reaches a preset threshold value, the device is unlocked. On the other hand, when the similarity does not reach the preset threshold value, fingerprint unlocking fails, and the device may record an unlocking failure. When fingerprint authentication produces multiple unlocking failures, the device may be disabled, and, in some cases, data erasing measures may also be initiated. In particular, portable devices, such as cell phones or smartphones, may initiate fingerprint authentication a number of times while being carried in a pocket, or while being positioned in a manner that activates the fingerprint sensor. Inevitably, this will result in a number of unlocking failures, which can lead to undesirable data erasure or lockout, or at the very least will unnecessarily increase battery consumption. Therefore, there is a need for improved methods directed to fingerprint authentication.